What type of threat is characterized by software secretly collecting data about user activity on a computer?

The correct choice identifies spyware, which is specifically designed to gather information about a user’s activities on a computer without their knowledge. Spyware can track browsing habits, capture keystrokes, and monitor other interactions with the system, often sending this data back to a third party. This type of threat can significantly infringe on user privacy and security, as it typically operates in the background without any visible signs of its presence.

In contrast, while adware also collects data and may serve advertisements based on user behavior, its primary purpose is to generate revenue through advertising rather than covertly spying on user activities. A virus is malicious software that can replicate itself and spread to other devices, often causing harm to systems, whereas a Trojan disguises itself as legitimate software to trick users into installing it, paving the way for other types of malware. Each of these threats operates differently, but spyware distinctly focuses on monitoring user actions silently and gathering data without permission.